Took a few hours on a lift but wasn't that big of an issue but did run into a few obstacles.

First I had to modify the air ducts (http://realoem.com/bmw/showparts.do?...51&fg=75&hl=23) to allow for the brackets to fit. I believe I only had to do this because my car is an 05 and BMW modified these ducts after 2003.5. Anyways, I have the CSL bumper, I only had to modify the driver side. I ended up cutting the cup flange protruding into engine bay and then using aluminium tape to cover the hole to seal the air duct that my intake uses. I will modify it yet again to delete the air duct all together and run straight piping all the way to the bumper.

Second I had to modify the mounting brackets since they were too long to fit over the sway bar bushing mount stud and the OEM oil cooler mount onto the radiator. Bench clamp and channel locks fixed that but made the oil cooler sit a little lower. Thus, mounted the Oil Cooler as far forward as possible to give the oil lines clearance from the front sway bar. Also cut the rubber skirts for the OEM oil cooler off the lower piece of the shroud (http://realoem.com/bmw/showparts.do?...=51&fg=75&hl=4).

Still wanted to use the OEM front aggregate protective plate (http://realoem.com/bmw/showparts.do?...=51&fg=80&hl=2), so I had to modify it to account for the larger oil cooler. The realoem diagram doesn't visually reflect the actual part. The plate is made of two pieces which are glued together. Inside the plate, there a piece of plastic you have to pull off to account for the larger oil cooler. Once you pull that off, with a little finesse of the plastic accounting for width of the new oil cooler you can put the front aggregate protective plate back on.

All in all, install was pretty straight forward. Hopefully some of this information helps.